var isCtrl = false;
document.onkeyup=function(e)
{
if(e.which == 17)
isCtrl=false;
}

document.onkeydown=function(e)
{
if(e.which == 17)
isCtrl=true;
if((e.which == 85) || (e.which == 67) && isCtrl == true)
{
// alert(‘Keyboard shortcuts are cool!’);
return false;
}
}